Dash-pot for scales.



' No. 893,386. PATENTBD JULY 14 i v R. T. SGHULZ & J. SIHLER.

DASH POT FOR SCALES w 00 k 3 m b u m 93 5 E R 1 m T 3 l 0Q \m m Q R l/J i APPLICATION FILED JAN 28 1907 F'x al- RICHARD TH. SOHULZ AND-JOHN SIHLER, OF DETROIT, MICHIGAN.

nA'sr'r-Po'r son scams.

Specification of Letters Patent.

Patented July 14, 1908.

Application filed January 28, 1907. Serial No. 864,559.

"State of Michigan, have invented a certain new and useful Improvement in Dash-Pots for Scales, and declare the following to be a full, clear, and exact descri tion of the same, such as will enable Others s 'lled in the art to which it pertains to make and use the same,

reference being had to the accompanying drawings, which form a part of this specification; 4

Our invention relates to an improvement in dash pots for checking the vibration of scales, and is shown in the accompanying drawings, in which,

' Figure 1 is an elevation partly in section of a scale showing the dash pot in position, Fig. 2 is a vertical section of-the pump showing parts in elevation; and, Fig. '3 is avertical sectional view of the piston, piston-stem, and connections.

Our invention relates to that class of devicesinwhich a. piston moved in a li uid, commonly oil or glycerin, is employe for checking the vibration of the 'parts of a scale, and its object is to provide automatic means for opening or closing the passageways through or around the piston as the oil becomes moreor less liquid due to the change.

in temperature.

In the drawings, A represents the frame. of

, a scale and a the beam-lever of the scale to usual form provided with a cap 6 that screws into the case and with the stem case b that extends a sufficient distance down into the case b to provide a rece tacle for the oil around the stem-case when t e scale isinverted in shiggping.

is the pump cylinder that extends downward from the case and in which the piston operates, the piston working in oil in this cylinder.

In construction, the piston F fits the cylinder only close enough so that slight resistance is offered to the movement of the piston up nut to iii: the

and downin the cylinder. In order to decrease this resistance, holes f are drilled throu h the piston, so that when the oil or other iquid used becomes thickened, means may be provided to allow it to pass through these openings to decrease the resistance to the piston. f is an additional piston or cap arranged on a stem f z to move to and from the main piston and to close the openings through the main piston, when it is desired to prevent oil from movin' throu h them.

he special mechanism y whic this dash pot is made automatic consists of means for closing or separating these two pistons-and consists of a case G connected to the upper end of the stem 9 by means of two nuts, one

g above the case, and one 9 o crating in' an' opening in the case, the two orming a setosition of the case on the stem g. In the owe'r'end of the case G is a 'fixed block 9 attachedto the case by the screw 9 and to the piston-stem f the construction being such that the main piston F moves at all times with the case G and moves up .and down with the beam-lever of th the stem f, and the piston or cap move together. it is a second pin set in t e block 3 and is merely a block H in osition.

h is a ru ber tube engaged at the lower end with the blockH by being slipped over the pin k and held to the in by turning down the rim h of the block The upper end of this tube is fixed to the lower end'of the short stem g. This rubber tube is filled with mercury and its position adjusted relative to the stem of the main piston and the case G by the adjustin nuts 9 and g the adjustment being such t at in a moderate or normal tem erature the expansion of the mercury wil hold the additlonal piston or cap f a slight distance away from the main piston, but so that in cold weather when the mercury contracts, the block H will be drawn up and the cap f so far separated from the main piston as to allow the thickened liquid to pass more freely through the main piston. In warm weather the mercury will expand sufliciently to close the cap f against the main piston and shut off the flow of the liquid through the piston entirely.

h is a spiral spring placed around the rubguigle to help keep the her tube to protect it and serves to draw the block H up against the mercury, while at opening of thermostatic means for Opening and closin said openin 2. Ina ash pot, acyfinder, a piston, there being an opening from one end of the cylinder to the other, and thermostatic means for increasing and decreasing the opening from 'one end of the cylinder to the other, substantially as described.

3. In a dash pot, the combination with a cylinder and a piston, of thermostatically operating means constructed and arranged for cooperation with the piston to retain the liquid of the dash pot upon-one side of the piston or to displace a portion of the liquid rom one side of the piston to the opposite side thereof.

4. In a dash ot for scales, the combination of a cylin er a piston provided withopenings, a cap and thermostatic means for actuating said cap to open and close said openlngs.

5. In a dash pot for scales, a cylinder a piston provided with; o enings, a pistonstem, a cap for closing t e OIiBIllllgS in the piston, a stem'for the cap s eeved on the piston-stem, and (thermostatic means for moving the sleeved stem to open and close the piston, substantially as described. I

6. In a dashpot for scales, a cylinder a piston having openings for circulating the iquidfrom one side of the piston to the other,- means for opening and closing said openin s, and thermostatic. means for operating t e opening and closing means comprising a rubber tube containing mercury, substan tially as described.

7. In a dash pot including a cylinder and a piston, means constructed and arranged for re ulating the flow of liquid 'from one side 0? the piston to the other, and thermostatic means foroperating the regulating means. 1

' 8. A dash pot including a case and a com municatin piston chamber, said case havin a removab e closure provided with a centra opening and a depending piston rod case coincidmg with said openlng, a main piston rod extending through said openin and piston rod case said rod being provide with within the last mentioned casing to confine mercury and operating to automatically raise and lower said cap toward and away from the piston to 0 en and close the opening of the piston, and a s ielding means surrounding the mercury tube. 1

9. A dash pot including a case and a communicatin piston chamber, said case havin a removabde closure rovided with a centra opening and a de en ing piston rod case coinciding with sai opening, a main piston rod extendmg through said opening and piston rod case said rod being provided with a piston for reciprocation in said chamber, the piston having an opening therein,-a cap emracing the piston and provided with a stem, a casing having connection with the stem of said cap, a mercury tube confined within the last mentioned 'casin to confine mercury therein to automatica y raise and lower said cap toward andaway from the piston to open and close the opening of the piston.

10. In a dash pot, a cylindera piston provided with an o ening to permit of circulation of the liqui from one side of the iston t0 the other, means for opening and c osing said opening, and thermostatic means for o erating the o ening and closing means inuding a'tubu at mercury containing mem- In testimony whereof, we sign this specification in the resence of two witnesses. EICHARD TH. SGHULZ.

JOHN SIHLER. Witnesses: HENRY E. VILLEROT, S. E. THOMAS. 

